You can write slow code in any language, but you cannot write fast code in any language.
Every time I've said that languages like Python, JavaScript, and basically any other language where it's hard to avoid heap allocations, pointer chasing, and copious data copies are all slow, there are plenty of people who come out of the woodwork to inform me that it's all negligible.
To be a little bit fair to those people, I have been in many situations where people go "my matlab/python code is too slow, I must re-write it in C", and I've been able to get an order of magnitude improvement by re-writing the code in the same language. Hell I've ported terrible Fortran code to python/numpy and gotten significant performance improvement. Of course taking that well written code and re-writing that in well written C will probably give you a further order of magnitude improvement. Fast code in a slow language can beat slow code in a fast language, but obviously never beat fast code in a fast language.
I'm just a little bitter because of how many times I've been shushed in places like programming language subreddits and here when I've pointed out how inefficient some cool new library/framework/paradigm is. It feels like I'm either being gaslit or everyone else is in denial that things like excessive heap allocations really do still matter in 2025, and that JITs almost never help much with realistic workloads for a large percentage of applications.